In the state of the art, bobbins are moved from one side of the same machine to the other side, or from one machine to another, or from a pallet to the machine, by means of transport apparatus mounted on an upper trolley, sliding on the appropriate guides or rails which define the path which the apparatus can follow, or on a flag-type or pantograph arm or in any case by means of some kind of manipulator. These devices are provided with an arm at the lower end of which there is a shaft or mandrel attached, which shaft is suitable to be inserted into the central tube, or nucleus, of the bobbin. The arm is usually pivoting with respect to the sliding trolley and is articulated at one or more points, so as to allow the bobbin-bearing mandrel to be oriented at will in the free space, and thus to assume the desired angle, with respect to both the horizontal plane and the vertical plane.
When the apparatus reaches the predetermined destination, with the bobbin-bearing mandrel arranged substantially coaxial with the working mandrel, the bobbin is transferred manually from one mandrel to the other mandrel.
It is possible to do this without serious problems only if the bobbins weigh at most a few dozen kilograms.
With bobbins in the state of the art becoming larger and larger, with a weight which nowadays is in the region of hundreds of kilograms, transferring the bobbin manually from the mandrel to the working shaft is not only very difficult for those performing the operation, but also very dangerous. In fact, it could happen that, when the bobbin is axially thrust to detach it from the first mandrel and insert it into the other or working mandrel, the first mandrel, since in most cases it is mounted pivoting on the apparatus, might be axially displaced with respect to the second mandrel, with the consequent danger that, it the bobbin is not yet sufficiently inserted into the second mandrel, it might fall and consequently be damaged and cause damage in turn to persons or things.
Applicant has designed and embodied this invention to overcome these shortcomings and to obtain further advantages.